<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<style>
.v-lr { writing-mode:vertical-lr;  }
.v-rl { writing-mode:vertical-rl; }

div {
  width: 300px;
  height: 200px;
  background: #ddd;
  margin: 50px;
}
</style>
</head>

<body>

<div class="v-rl">
First part of the block.
<i id="test">New text inserted by script, to cause a reflow that slides the following lines.</i>
We will insert enough new content that it wraps onto additional lines.
<br><br>
Here is some more text that follows a forced break.
Observe what happens to it when text is added earlier.
</div>

</body>
</html>
